Carbureter



C. C. LITTLE.

CARBURETEH.

APPLICATION FILED 050.11.1917.

3 SHEETSSHEET I.

Patented Oct. 21

'F'IGLJFL 6 INJE J O FIGURE 1 BY [KM H .ATT RNE-y C. C LITTLE.

CARBURETER.

APPLICATION FILED 050.17, 19!].

Patenflwl Oct. 21, 1819.

FIGURE 14 T Z 5 A 4 4 a r l/$4 FIGURE 16 FIGURE 15 B (Z. flaw? H ATTORNEY rm: muwmn PI-ANOGRAPII c0, WASHINGTON. m c.

CHARLES c. LITTLE, or SAN JOSE, CALIFORNIA.

GARBURE'IER.

Specification of Letters Patent.

Patented Oct. 21, 1919,

.Applicationfiled December 17, 1917. Serial No. 207,614.

T 0 all whom it may concern:

Be it known that I, CIIARLEs O. LITTLE, a citizen of the United States, and resident of San Jose, in the county of Santa Clara and State of California, have invented oer tain new and useful Improvements in- Carbureters, of which the following is a specification.

My invention relates to carburetors, and particularly to that class of carburetors in which a plurality of fuel nozzles are used in conjunction with individual Venturi tubes controlled by a common throttle.

It is the object of my invention to provide an efficient, simple and economically constructed carbureter, of such design as to effectively meet the requirements of speed and load, as well as of fuel, temperature, atmospheric conditions and engine design.

Other objects of my invention are, to provide simple means for controllingthe dimensions of the carbureting chambers without departing to any great extent from the form of the natural vein of flow; to provide a plurality of mixing chambers of such dimensions that the speed of the mixture will be suflicient under all circumstances to hold the unvaporized fuel in suspension, and give suflicient time for complete vaporization and mixing before the mixture reaches the throttle; to provide compensating air ports directly under the control of the carbureting chamber regulating device and the throttle;

to provide a novel form of throttle which controls the output of the carbureting chambers and compensating air ports, so that one chamber may be partially opened before the chamber preceding it in action is entirely opened and so that a discharge passage is provided which closely approaches the form of the true vein of flow; to provide means for introducing Water into the mixture in quantities directly proportional to the amount of air and fuel; to provide deflectors within the throttle to form symmetrical passages and eliminate pockets to provide a carbureter which develops high vapor speeds with relatively small voluiiietric' loss by eiiiiiinating sharp-bends, projections and pockets ifi: the mixture passages arid by pro:

viding a venturi-like construction of the carbureting chambers and throttle.

With the foregoing and other objects in View the invention resides in the combination and arrangement of parts and in details of construction hereinafter described and claimed, it being understood that changes Fig. 6 is a detail elevation of the defiect- 7 ing member.

Fig. 7 is a sectional view on line AA of Fig. 1.

Fig. 8 is a view similar to Fig. 7 but showing a modification including water nozzles.

Fig. 9 is a. view similar to Fig. 7- but showing a modification in'Which the second tube is utilized as an auxiliary air inlet. Fig. 10 is a view similar to Fig. 7 but showing a modification in which two auxiliary air inlets are provided.

Fig. 11 is a sectional view through a sector shaped throttle adapted for use on my improved carbureter.

Fig. 12 is a right side elevation of Fig. 11.

Fig. 13 is a vertical section through a. carbureter embodying an additional form of the device for regulating the size of the air passages in the restricted portions of the tubes. 7 I v,

Fig. 14 is a sectional view on line BB ofFig.13. r

Fig. 15 is a vertical section through a car-j bureter showing another location of. the throttleland another regulating dev'ic'z'e.v

rig;- is Vermeer station threugh a car-- i 1 bureter embodying another form of the device for regulating the size of the air passage in the restricted portion of the tubes.

Fig. 17 is a detail elevation of the regulating device shown in Fig. 16.

Fig. 18 is a sectional view on line CC of the regulating device shown in Fig. 13.

Similar characters of reference refer to similar parts throughout the several views.

In the drawings, 1 indicates the carbureter casing, 2 the float chamber, 3 the Venturi tubes forming air inlets at, restricted throat-portions 5, carbureting chambers 6 and mixing chambers '7, the several tubes being separated by webs 8. At 9 is a fuel conduit connected to chamber 2 by orifice 10. In the restricted portions of tubes 3 are positioned fuel nozzles 11 connected to conduit 9 by conduits 12. At 13 is shown a water conduit connected to a source of supply not shown and discharging into tubes 3 through nozzles 1%.

In the present instance the size of passages 5 is regulated by members 15 secured to shaft 16 which is journaled in casing 1 and operated by lever 17, the lever 17 operating to throw members 15 forward as into the position shown in dotted lines at 18, and to retract the same. Guard members 19 are hinged to members 15 as at20, their upper and free ends moving freely in pockets 21 formed in casing 1 and held therein by plates 22. v

At 23 is shown a cylindrical throttle mounted on shaft 24 which is operated in any suitable manner not shown. Throttle 23 has a number of slots formed in its circumference as at 25, each slot corresponding in width to the tube in connection with which it operates and of which it forms a continuation, the first slot being referred to as 25, the second as 25 and so on. As one example of the manner in which the throttle may operate, the throttling edge of slot 25 is so positioned as to come'into operation at a predetermined time after the throttling edge of slot 25 has come into operation, and preferably so positioned with relation to the throttling edge of slot 25 that, in conjunction with the flatter contour of its bottom, a larger discharge passage is formed when the throttle is revolved through a given are than is formed by the throttling edge of slot 25 when revolved through an equal are. This is clearly shown in Figs. 2 and 3 in which passage D is shown to be larger than passage C although arcs E and F are equal.

At 26 are shown curved members or deflectors fitted into tubes 3 and projecting forwardly into slots 25 to 25" inclusive so as to form continuous passages for the mixture by cutting ofi the pockets formed by portions of said slots, and thereby form a H portion ofthe Venturi-like passages through throttle 23. The shape of the true vein of flow of fluid passing through these tubes or passages is determined by the general contour of each passage and consequently it is desirable that all pockets or portions out of the direct path of the moving fluid be closed off in some manner such as that described. The engine passage 27 is preferably made large in proportion to the cross-sectional areas of the various tubes, the throttle opening its several slots thereinto through port 28.

The embodiment shown in Fig. 8 indicates how the carbureter may be fitted with fuel nozzles and with water nozzles 14 adapted to cooperate therewith.

The embodiment shown in Fig. 9 shows how the carbureter may be fitted with fuel nozzles in .all of the tubes except the second which is used as a compensating air inlet port.

The embodiment shown in Fig. 10 shows how the device may be fitted with a plural ity of compensating air inlet-s.

In Figs. 11 and 12 are shown a sector shaped throttle 29 mounted on shaft 30 and having its throttling edge 31 curved substantially as shown so that as it opens, as indicated in dotted lines at 32, it partially opens the second tube before entirely opening the first tube. In order that there may be a minimum of lag in the opening of the second tube, the top of the web between the first and second tubes is chamfered as shown at 33.

Figs. 13 and let show another form of the device used for regulating the flow of air through the restricted portions of the tubes and consists of a sliding member 34 provided with vertical slots 35 adapted to engage webs 8 and operated by arm 36 secured to shaft 37, the outer end of arm 36 operating in recess 38 in member 3% and the said slots permitting member 3t to be moved forward between webs S as to a position indicated in dotted lines at '18. Guides are shown at 39 on member 3 1 and guide-slo are shown at 1L0 in carbureter casing 1. The members 19 are hinged to member 34 and? are constructed and operated as described in connection with Fig. 1.

The embodiment shown in Fig. 15 shows a combination of air regulating device and throttle without intervening tubes. In this embodiment the throttle is similar to that described in connection with Fig. 1 but the air regulating device consists of a plate 41 slidably mounted in casing 1 and having a shoe 4E2 mounted on resilient arm 13 positioned in each slot. The shoe 42 engages the bottom of the slot 25 and is operated by forcing it forwardly so as to ride up on its heel 44: thereby narrowing the passage 45 as indicated in dotted lines at 46. A means of operating plate 41 consists of a shaft 17 journaled in casing 1 and operating an eccentric pin 48 which in turn operates in slot 19 in plate 41. 7

Figs. 16 and 17 show a rotary member adapted to be used as a regulating device for altering the size of the air passages adjacent the fuel nozzles, the rotary member 50 being journaled in casing 1 and having slots 51 formed therein to operate in conjunction with each nozzle, the result obtained being substantially the same as that obtained by using member 15 in Fig. 1.

Assuming, now, that the engine is running at its slowest speed without load, with fuel of average weight and viscosity, and

under average conditions of temperature and I atmospheric pressure.

The adjusting member 15 would occupy a position intermediate its range of motion as shown in dotted lines at 18, and'the throttle would be openedso that the first slot would partially open into the discharge port. At this slow speed the carbureter should deliver a rich mixture partly be-- cause a somewhat rich mixture is desirable 1n the cyhnders and partly to compensate for the inevitable air leakage into the cylinders. I therefore make the first tube 3 small and supply it with a relatively large fuel nozzle. As the throttle is opened further and the engine speed increases the carburetershould deliver a leaner mixture. The tendency of the single tube will be to deliver a richer mixture on account of the increased air speed past the nozzle. To counteract thistendency, as well as to adjust the mixture to the requirements of'the increased speed, I arrange that the second slot of the throttle start to open as soon as the first slot'opens beyond the slow running position. As the second tube is of relatively larger area the throttle will open to some distance before the air will pass the fuel nozzle in said second tube with suflicie'nt velocity to cause fuel to flow therefrom. The second tube therefore may be considered as a compensating air, inlet during the first stages of'its opening and can be made to deliver air to the mixture from the first tube in any -desired proportions by variation in the depth contour of the two slots.

The second tube is so proportioned with regard to the area of its cross-section and the size of its fuel nozzle that fuel will flow in proper quantity when needed. When more speed is required further rotation of the throttle will successively open the other tubes, each one of which with its fuel nozzles, is so proportioned that its output added to the output of the tubes preceding it in action, will form a correct mixture.

It is desirable in order to insure smoothness of action; that a certain amount of throttle lead'such as described in connection with the first two tubesbe applied to the succeeding tubes, but the lead need not be so great and becomes of less importance the greater the number of tubes opened.

In some cases in order to carry out the mixture compensations in the first two tubes, I prefer to leave the second tube without a fuel supply as in Fig. 9. In this construction the second tube is essentially a compensating air inlet, but has'the advantage of admitting air under the same frictional resistance as the other tubes and is controlled by the adjusting device 15 and the throttle 23 without additional mechanical complications. r

The function of the carbureting chamber adjustment 15 is to providemeans for adjusting the carbureter for variations in fuel, temperature, atmospheric pressure or engine design by varying the sizerof the air passages in the restricted portions of the tubes. close off the space back of member 15 from the interior of the tube and thereby prevents member 15 from closing the said passage in case of an explosion in the'carbureter,

and completes the venturi-like form of the chamber. As an example of its operation, a fuel rich in combustible elements would require more oxygen to burn it and the adj usting member would be moved back to enlarge the passages with the dual result that more air would beadmitted andthere would be less suction on the nozzles, or if the en gine were adjusted to run at a high temperature and the temperature were lowered,

member 15 would be moved forward to compensate for the'decreased flow of fuel due to its greater viscosity. While it is not intended that this adjustment be used con stantly in operating the engine, it is obvious that it may be used at any time to vary the The hinged member 19 serves to proportions of the mixture to meet unusual.

requirements of load or speed.

So far I have consldered only compensation of mixture for various speeds.

1 The VGIltllIl-like form of the carbureting' chamber, as well asthe avoidance of bends, projections and pockets, allows of the use of creasing volumetric efficiency.

' I also depend upon'the fact that the fric-z In case of heavy loads w1th the engine runn ng.

high air speeds without prejudicially de- 7 tion of the fuel stream is proportionally less at low speeds than that of the air stream, and the small nozzles and long fuel tubes make it possible to provide for almost any amount of frictional resistance by simply varying their caliber and length without further mechanical complications.

When my carbureter is constructed substantially as shown in Fig. 1 and is connected to discharge into an engine passage of relatively large capacity it is possible to damp out much of the engine pulsation and surging which is so disturbing to carbureter action. This result is secured because the relatively small mass moving at high velocity in the Venturi tube encounters a larger mass in the engine passage, the movement of which is slow.

I claim 1. A carbureter including a plurality of Venturi tubes, a full nozzle operatively positioned in one side of each of said tubes, manually operated means for simultaneously altering the size of the air passages adjacent said nozzles, and a single independently operated throttle controlling the flow of mixture from said tubes and having its throttling edge formed so as to partially throttle one tube before wholly throttling an adjoining tube.

2. In a carbureter having a casing provided with a plurality of fluid intake passages, a cylindrical throttle operatively mounted in said casing and having a plurality of individual, parallel, circumferentially disposed slots formed therein, each slot forming a continuation of one of said passages, of varying depth contour and cooperating with the inner surface of said casing to form a passage of varying cross-sectional area.

3. In a carbureter having a casing provided with a plurality of fluid intake passages, a cylindrical throttle operatively mounted in said casing and having a plurality of individual parallel, circumferentially disposed slots formed therein, each slot forming a continuation of one of said passages, of varying depth contour, cooperating with the inner surface of said casing to form a passage of varying cross-sectional area, and having a throttling edge adapted to open or close its respective passage before the passage preceding it in action is entirely opened or closed.

4. A carbureter including a plurality of Venturi tubes, a fuel nozzle operatively positioned in one side of each of said tubes, manually operated means for simultaneously altering the size of the air passages adjacent said nozzles, a single independently operated throttle controlling the flow of mixture from said tubes and having its throttling edge formed so' as to partially throttle one tube before wholly throttling an adjacent tube, and a water supply nozzle operatively positioned in each tube and coacting with the fuel nozzle in said tube.

5. A carbureter including a plurality of Venturi tubes, fuel nozzles operatively positioned with relation to the restricted portions of two or more of said tubes, means for simultaneously altering the size of the air passages in the restricted portions of two or'more of said tubes, said means comprising a manually operated compound choke-valve, the free end of each member of said compound valve having a guard member attached thereto, the free end of said guard member cooperating with the side of its respective tube to close off the rear of said member from the interior of said tube.

6. A carbureter including a plurality of Venturi tubes, fuel nozzles operatively p0- sitioned with relation to the restricted portions of two or more of said tubes, means for simultaneously altering the size of the air passage in the restricted portions of two or more of said tubes, and a single independently operated throttle for opening or'closing said tubes, said throttle comprising a cylindrical member operatively j ournaled in said carbureter and having a plurality of slots formed in its circumference, each slot being adapted to cooperate with one of said tubes and forming a continuation thereof and having a throttling edge adapted to partially open or close its respective tube before the tube preceding it in action is entirely opened or closed, and a deflecting member positioned in each slot to form a passage therein conforming substantially to the shape of the true vein of flow.

7 A carbureter having a plurality of parallel webs fixedly attached thereto, a fuel nozzle operatively positioned between each two of said webs, an adjustable member provided with slots adapted to engage said webs, means for adjusting said adjustable member, and a throttle adapted to successively uncover the passages formed by said webs and having its throttling edge so formed as to partially throttle one of said. passages before wholly throttling an adjacent passage.

8. In a carbureter having a plurality of Venturi tubes and having a cylindrical throttle provided with a plurality of slots formed in the circumference thereof and operatively mounted with relation to said tubes, a deflecting member positioned in each slot to form a passage therein conforming substantially to the shape of the true vein of flow.

9. A carbureter having a single air inlet opening, a plurality of Venturi tubes communicating directly therewith, a fuel nozzle operatively positioned in each tube, manu ally operated means for simultaneously altering the size of each tube adjacent its respective nozzle, independently operable means for partially opening or closing one tube before entirely opening or closing the tube preceding it in action, and means operatively positioned With relation to each of said above mentioned means and said tubes to form continuous passages conforming substantially to the shape of the true Vein 10 CHARLES C. LITTLE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

, Washington, D. G. 

